The Milan exchange. (Milan, Gibson County, Tenn.) 1874-1978, 1887-05-14

ton of rays Of light by a more convex
surface being a necessity from water
into the eve. But of all fishes, the.
anableps has perhaps the most note
worthy eye. The creature swims half
above the surface of the water, and the
eye is divided horizontally into two
portions, the one for seeing in the
water, the other in the air. Insects,
again, are provided with the most Won
derful organs of sight. Their nature
and construction are different from all
others, and two kinds of eyes, the SIM
pie and the composite, are united in
one small creature. The simple eyes
are generally three, and are situated on
the crown of the head between the
more elaborate organs of sight. The
structure of each kind is perfectly
distinct. The composite eyes are
marvellous combination of null
tiplicity of perfect eyes, which
may be seen in microscopic
examination of the cornea. The cornea
then stands revealed as mass Of many
thousand regularly disposed hexagonal
facets, each of which is in itself per,
feet eye. In the head of a butterfly,
nearly thirty-fve thousand have been
counted; and some insects are suppos-
ed to be still more numerously sup
piled. The simple eyes, on the other
hand, are simple, as their name i'm
plies; each simple eye is single organ
the cornea exhibiting no appearance o!
facets. The uses of these eyes, which
the unwearying researches of natural
lists have now established, are as inter-
esting as they are extraordinary.
Reaumur. in his well-known expert
ments, first smeared the com.
pound eyes of insects with
paint, and next the simple
eyes; and discovered that the COM
pound eyes for horizontal sight, and
the simple for vertical; since those
whose compound eyes were closed
flew straight up into the air until they
were lost to sight, and those whose
simple eyes were operated upon winged
their way on all sides amongst the
flowers around, but neither assembled
into the air nor flew far away. Com
pound eyes, in addition, are supposed,
and with good reason, to have the
power of magnifying; and a comical
story is recorded of Puget adjusting
the eye of flea in such way as to see
objects through it, and finding that a
soldier appeared like an army of pig
mics, for what it multiplied it dimin-
ished; and the flame of candle seem
ed the illumination of thousand fairy
lamps.
Equally unmistakable evidences OF
design are found in the sharpness OF
sight accorded to some creatures, and
the deficiency in others. Sir John Lub-
book has shown Us hSsT the exception.
ally intelligent ant race depends en-.
tirely on the sense of smell as a guide
to its movement, and that so effectua,
and unerring is the sense of smell, thai
sight is scarcely needed; and that, il
fact, the workers have in most cases nj
vision at all, though they are descended
from flying insects with highly devel
oped eyes. The antenn@ have devel
| nnnH RI c1rnh nxyfn 10, To-
sight useless adjunct, and where
through accident or otherwise, the an
tenn@ are wanting, the ant is "as help
less as a blind man among ourselves.
The opposite extreme to the ant in
visual sense is to be found in one o
two kinds of birds. A hawk can spy
lark upon piece of earth almost exact
ly the same color at twenty times tn
distance it is perceptible to a man o
dog; a kite soaring out of human sigh
can still distinguish and pounce upo
lizards and field mice on the ground
and the distance 5Stwhich vultures an
eagles can spy out their prey is almos
incredible. Recent discoveries, an
especially Darwin's observations, hay
inclined naturalists to the belief tina
birds of prey have not the acut
sense of smell with which they wer
once accredited. Their acute sigh
seems better to account for thei
actions, and they appear to be guide
by sight alone, as they never sniff an
thing, but dart straight at the objet
of their desire. Their counterparts i
the ocean, however, undoubtedly Sc
and smell equally well, BIT
are more guided by smell tina
sight. In both sharks and rays, tn
eyes are good, and have a most di
tinct expression; though, since the
scent their prey from distance, an
: swim up to it with great rapidit1
smell" as Lacapede says, ''may /
called their real eye" Smell, in NJ
: Herbert SpCnoN's definition, is antic
patary taste; and the manner in whic
: sight, as the dominating sense, is sui
.4;4,,tsl e., 49,. Ill Al l.. IL -. Al. - -